nytimes.com – POTTERSVILLE, N.Y. — You could forgive Clarke Dunham if the events of the last few months have him feeling as if he were a character in a Frank Capra movie — special dispensation, naturally, accorded to anyone who calls Pottersville home. Faced with financial difficulties, he and his wife, Barbara, were about to lose Tthe Station, a model railroad that attracted millions during the holidays to the former Citigroup building, in Midtown Manhattan, during its 17-year run there.